Naomi asks Bailey how Archer and Sam are doing, and Bailey gives her a whole barrage of yelling, classic Bailey style. Naomi's all, "Are you this way with everyone, or just me?" However, Mark (Eric Dane) shows up and tells Naomi that she and Archer being together gives him hope that things might actually be real between himself and Little Grey, or "the pre-schooler," as Naomi calls her.

The problem that Addison and Derek find with Jen is that when he nicked her aneurysm during her craniotomy, she lost a lot of blood and had to have a transfusion. But for some reason, the baby is not accepting the blood, and mother and baby are going into heart failure. It's very bad, and if they don't deliver the baby now, then they both might die. However, even if they do deliver, the fetus is only at 24 weeks, which doesn't give it very good odds of surviving. Addison and Derek give the bad news to Jen, but she wants to leave the baby in for two more weeks. Without consulting Addison, Derek says that they can perform an in utero blood transfusion, which Jen wants to do, despite Addison's assertions that the risks for both mother and baby are too high.

But you see, Derek blames himself for Jen and the baby's conditions because he was the one who nicked her aneurysm in the first place. If either dies, it'll be his fault, so he begs Addison to do the in utero procedure. She agrees. All throughout the surgery, Addison bickers with Derek about how he cornered her into doing the operation just like that time, years ago when they were married, he cornered her into making the Thanksgiving turkey. It turned into a disaster, and his sister contracted salmonella. Derek emerged the hero of the fiasco by making hot dogs for everyone. Fortunately, they save both Jen and the baby, so they are both heroes in this case. While they are cleaning up, Derek admits that McMommy hated her all these years, which is why she never gave him her engagement ring to give to Addison.

It turns out that Sam needs a special inhaler because he's allergic to the regular kind, and that's why he had the asthma attack. He crows to Naomi that his passing out was a symptom of actual physical problems, and not wishy-washy, weepy emotional problems arising from seeing his ex-wife with another man. "I'm a man! With asthma!" he cries, fist-bumping Bailey. Okay, let me just say that even if this were the case, which I'm not really that inclined to believe, this being a Shonda Rhimes show and all, that is not a nice thing to say to one's wife or ex-wife. Inappropriate much? Sometimes, these Grey's Anatomy/Private Practice people just irk me with their rudeness.

Richard and Naomi bring the CT scans to Archer, who reads his own scans and sees more cysts. He thinks he's going to die. Wait, didn't he say that his vision was funny? Also? Isn't Richard the freaking chief of surgery? Can't he freaking read the scan himself, instead of letting the patient make the diagnosis, even if the patient happens to be a world-class neurologist?